scholarly journals Multilevel regulation of Wnt signaling by Zic2 in colon cancer due to mutation of β-catenin

2021 ◽  
Vol 12 (6) ◽  
Author(s):  
Zhengshui Xu ◽  
Jianbao Zheng ◽  
Zilu Chen ◽  
Jing Guo ◽  
Xiaopeng Li ◽  
...  

AbstractZinc-finger of the cerebellum 2 (Zic2) is widely implicated in cancers, but the role of Zic2 in tumorigenesis is bilateral. A recent study indicated that Zic2 could render colon cancer cells more resistant to low glucose-induced apoptosis. However, the functional roles of Zic2 in colon cancer and the underlying molecular mechanism remain elusive. Herein, we demonstrated that Zic2 was highly expressed in colon cancer tissues and correlated with poor survival. Knockdown of Zic2 inhibited colon cancer cell growth, arrested the cell cycle transition from G0/G1 to S phase, and suppressed tumor sphere formation in vitro; in addition, silencing Zic2 retarded xenograft tumor formation in vivo. Consistently, ectopic expression of Zic2 had the opposite effects. Mechanistically, Zic2 executed its oncogenic role in colon cancer by enhancing Wnt/β-catenin signaling. Zic2 directly binds to the promoter of Axin2 and transcriptionally represses Axin2 expression and subsequently promotes the accumulation and nuclear translocation of β-catenin. Meanwhile, Zic2 could activate Wnt signaling by interacting with β-catenin. Intriguingly, in HCT116 cells with intrinsic Ser45 mutation of β-catenin, which blocks the degradation-related phosphorylation of β-catenin by CK1, modified Zic2 expression did not affect the protein level of β-catenin. Altogether, our findings uncover a novel multilevel mechanism for the oncogenic activity of Zic2 in colon cancer and suggest Zic2 as a potential therapeutic target for colon cancer patients.

2018 ◽  
Vol 115 (29) ◽  
pp. E6760-E6769 ◽  
Author(s):  
Jiuli Zhou ◽  
Yongji Zeng ◽  
Lian Cui ◽  
Xingcheng Chen ◽  
Seth Stauffer ◽  
...  

Zyxin is a member of the focal adhesion complex and plays a critical role in actin filament polymerization and cell motility. Several recent studies showed that Zyxin is a positive regulator of Yki/YAP (Yes-associated protein) signaling. However, little is known about the mechanisms by which Zyxin itself is regulated and how Zyxin affects Hippo–YAP activity. We first showed that Zyxin is phosphorylated by CDK1 during mitosis. Depletion of Zyxin resulted in significantly impaired colon cancer cell proliferation, migration, anchorage-independent growth, and tumor formation in xenograft animal models. Mitotic phosphorylation is required for Zyxin activity in promoting growth. Zyxin regulates YAP activity through the colon cancer oncogene CDK8. CDK8 knockout phenocopied Zyxin knockdown in colon cancer cells, while ectopic expression of CDK8 substantially restored the tumorigenic defects of Zyxin-depletion cells. Mechanistically, we showed that CDK8 directly phosphorylated YAP and promoted its activation. Fully activated YAP is required to support the growth in CDK8-knockout colon cancer cells in vitro and in vivo. Together, these observations suggest that Zyxin promotes colon cancer tumorigenesis in a mitotic-phosphorylation-dependent manner and through CDK8-mediated YAP activation.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kazim Husain ◽  
Domenico Coppola ◽  
Chung S. Yang ◽  
Mokenge P. Malafa

AbstractThe activation and growth of tumour-initiating cells with stem-like properties in distant organs characterize colorectal cancer (CRC) growth and metastasis. Thus, inhibition of colon cancer stem cell (CCSC) growth holds promise for CRC growth and metastasis prevention. We and others have shown that farnesyl dimethyl chromanol (FDMC) inhibits cancer cell growth and induces apoptosis in vitro and in vivo. We provide the first demonstration that FDMC inhibits CCSC viability, survival, self-renewal (spheroid formation), pluripotent transcription factors (Nanog, Oct4, and Sox2) expression, organoids formation, and Wnt/β-catenin signalling, as evidenced by comparisons with vehicle-treated controls. In addition, FDMC inhibits CCSC migration, invasion, inflammation (NF-kB), angiogenesis (vascular endothelial growth factor, VEGF), and metastasis (MMP9), which are critical tumour metastasis processes. Moreover, FDMC induced apoptosis (TUNEL, Annexin V, cleaved caspase 3, and cleaved PARP) in CCSCs and CCSC-derived spheroids and organoids. Finally, in an orthotopic (cecum-injected CCSCs) xenograft metastasis model, we show that FDMC significantly retards CCSC-derived tumour growth (Ki-67); inhibits inflammation (NF-kB), angiogenesis (VEGF and CD31), and β-catenin signalling; and induces apoptosis (cleaved PARP) in tumour tissues and inhibits liver metastasis. In summary, our results demonstrate that FDMC inhibits the CCSC metastatic phenotype and thereby supports investigating its ability to prevent CRC metastases.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Dan Lei ◽  
Wen-Ting Yang ◽  
Peng-Sheng Zheng

AbstractHomeobox B4 (HOXB4), which belongs to the homeobox (HOX) family, possesses transcription factor activity and has a crucial role in stem cell self-renewal and tumorigenesis. However, its biological function and exact mechanism in cervical cancer remain unknown. Here, we found that HOXB4 was markedly downregulated in cervical cancer. We demonstrated that HOXB4 obviously suppressed cervical cancer cell proliferation and tumorigenic potential in nude mice. Additionally, HOXB4-induced cell cycle arrest at the transition from the G0/G1 phase to the S phase. Conversely, loss of HOXB4 promoted cervical cancer cell growth both in vitro and in vivo. Bioinformatics analyses and mechanistic studies revealed that HOXB4 inhibited the activity of the Wnt/β-catenin signaling pathway by direct transcriptional repression of β-catenin. Furthermore, β-catenin re-expression rescued HOXB4-induced cervical cancer cell defects. Taken together, these findings suggested that HOXB4 directly transcriptional repressed β-catenin and subsequently inactivated the Wnt/β-catenin signaling pathway, leading to significant inhibition of cervical cancer cell growth and tumor formation.


2020 ◽  
Vol 2020 ◽  
pp. 1-7 ◽  
Author(s):  
Guifeng Wang ◽  
Ning Ma ◽  
Feng He ◽  
Shosuke Kawanishi ◽  
Hatasu Kobayashi ◽  
...  

Taurine (2-aminoethane-sulfonic acid) is a type of amino acids and has numerous physiological and therapeutic functions, including anti-inflammation. However, there are few studies on the anticancer action of taurine. Our previous studies have demonstrated that taurine exhibits an apoptosis-inducing effect on human nasopharyngeal carcinoma cells in vitro. In this study, we have investigated whether taurine has an anticancer effect, using azoxymethane (AOM)/sulfate sodium (DSS)- induced mouse model for colon carcinogenesis. All mice, except those in control group, received a single intraperitoneal injection of AOM and DSS in the drinking water for 7 days twice, with 1-week interval. After the first DSS treatment, mice were given distilled water (model group) or taurine in the drinking water (taurine group) ad libitum. No tumor was observed in the control group. Taurine significantly suppressed AOM+DSS-induced tumor formation. Histopathological examination revealed AOM/DSS treatment induced colon cancer in all mice (8/8, 100%), and taurine significantly inhibited the progression of colon cancer (4/9, 44.4%). Taurine significantly attenuated cell proliferation in cancer tissues detected by Ki-67 staining. Taurine significantly increased the levels of an apoptosis marker cleaved caspase-9 and tumor suppressor protein PTEN. This is the first study that demonstrated that taurine significantly reduced carcinogenicity in vivo using AOM/DSS-induced colon cancer mouse model.


2019 ◽  
Vol 20 (21) ◽  
pp. 5391 ◽  
Author(s):  
Wörthmüller ◽  
Salicio ◽  
Oberson ◽  
Blum ◽  
Schwaller

Malignant mesothelioma (MM) is an aggressive asbestos-linked neoplasm, characterized by dysregulation of signaling pathways. Due to intrinsic or acquired chemoresistance, MM treatment options remain limited. Calretinin is a Ca2+-binding protein expressed during MM tumorigenesis that activates the FAK signaling pathway, promoting invasion and epithelial-to-mesenchymal transition. Constitutive calretinin downregulation decreases MM cells’ growth and survival, and impairs tumor formation in vivo. In order to evaluate early molecular events occurring during calretinin downregulation, we generated a tightly controlled IPTG-inducible expression system to modulate calretinin levels in vitro. Calretinin downregulation significantly reduced viability and proliferation of MM cells, attenuated FAK signaling and reduced the invasive phenotype of surviving cells. Importantly, surviving cells showed a higher resistance to cisplatin due to increased Wnt signaling. This resistance was abrogated by the Wnt signaling pathway inhibitor 3289-8625. In various MM cell lines and regardless of calretinin expression levels, blocking of FAK signaling activated the Wnt signaling pathway and vice versa. Thus, blocking both pathways had the strongest impact on MM cell proliferation and survival. Chemoresistance mechanisms in MM cells have resulted in a failure of single-agent therapies. Targeting of multiple components of key signaling pathways, including Wnt signaling, might be the future method-of-choice to treat MM.


2021 ◽  
Vol 12 ◽  
Author(s):  
Xue Hu ◽  
Fangzhou Jiao ◽  
Lan Zhang ◽  
Yingan Jiang

Liver cancer is the sixth most commonly diagnosed cancer and the fourth leading cause of cancer death. Most (75–85%) primary liver cancers occurring worldwide are hepatocellular carcinoma (HCC). The development of resistance and other drug related side effects are the prime reasons for the failure of treatment. Therefore, developing high-efficacy and low-toxicity natural anticancer agents is greatly needed in the treatment of HCC. Dihydrotanshinone (DHTS) is widely used for promoting blood circulation and antitumor. The aim of the present study was to investigate the effect and mechanism of DHTS-induced apoptosis of HCC, both in vitro and in vivo. We found that DHTS inhibited the growth of several HCC cells (HCCLM3, SMMC7721, Hep3B and HepG2). DHTS induced the apoptosis of SMMC7721 cells. Immunofluorescence results have showed that DHTS decreased STAT3 nuclear translocation. Moreover, Western blot results have demonstrated that DHTS suppressed the activation of JAK2/STAT3 signaling pathway. In addition, xenograft results have showed that DHTS suppressed tumor growth of SMMC7721 cells in vivo by inhibiting the p-STAT3. Thus, we demonstrated that DHTS could inhibit HCC by suppressing the JAK2/STAT3 pathway. DHTS has potential to be a chemotherapeutic agent in HCC and merits further clinical investigation.


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